diff --git a/hardware/arduino/avr/cores/arduino/WString.cpp b/hardware/arduino/avr/cores/arduino/WString.cpp
index 8c85cc592..48c30df77 100644
--- a/hardware/arduino/avr/cores/arduino/WString.cpp
+++ b/hardware/arduino/avr/cores/arduino/WString.cpp
@@ -325,14 +325,14 @@ unsigned char String::concat(unsigned long num)
 unsigned char String::concat(float num)
 {
 	char buf[20];
-	char* string = dtostrf(num, 8, 6, buf);
+	char* string = dtostrf(num, 8, 2, buf);
 	return concat(string, strlen(string));
 }
 
 unsigned char String::concat(double num)
 {
 	char buf[20];
-	char* string = dtostrf(num, 8, 6, buf);
+	char* string = dtostrf(num, 8, 2, buf);
 	return concat(string, strlen(string));
 }
 
diff --git a/hardware/arduino/avr/cores/arduino/WString.h b/hardware/arduino/avr/cores/arduino/WString.h
index 44a841930..b3b9f1427 100644
--- a/hardware/arduino/avr/cores/arduino/WString.h
+++ b/hardware/arduino/avr/cores/arduino/WString.h
@@ -69,8 +69,8 @@ public:
 	explicit String(unsigned int, unsigned char base=10);
 	explicit String(long, unsigned char base=10);
 	explicit String(unsigned long, unsigned char base=10);
-	explicit String(float, int decimalPlaces=6);
-	explicit String(double, int decimalPlaces=6);
+	explicit String(float, int decimalPlaces=2);
+	explicit String(double, int decimalPlaces=2);
 	~String(void);
 
 	// memory management
diff --git a/hardware/arduino/avr/cores/robot/WString.cpp b/hardware/arduino/avr/cores/robot/WString.cpp
index 8c85cc592..48c30df77 100644
--- a/hardware/arduino/avr/cores/robot/WString.cpp
+++ b/hardware/arduino/avr/cores/robot/WString.cpp
@@ -325,14 +325,14 @@ unsigned char String::concat(unsigned long num)
 unsigned char String::concat(float num)
 {
 	char buf[20];
-	char* string = dtostrf(num, 8, 6, buf);
+	char* string = dtostrf(num, 8, 2, buf);
 	return concat(string, strlen(string));
 }
 
 unsigned char String::concat(double num)
 {
 	char buf[20];
-	char* string = dtostrf(num, 8, 6, buf);
+	char* string = dtostrf(num, 8, 2, buf);
 	return concat(string, strlen(string));
 }
 
diff --git a/hardware/arduino/avr/cores/robot/WString.h b/hardware/arduino/avr/cores/robot/WString.h
index 4b9e64e0b..0404f767a 100644
--- a/hardware/arduino/avr/cores/robot/WString.h
+++ b/hardware/arduino/avr/cores/robot/WString.h
@@ -69,8 +69,8 @@ public:
 	explicit String(unsigned int, unsigned char base=10);
 	explicit String(long, unsigned char base=10);
 	explicit String(unsigned long, unsigned char base=10);
-	explicit String(float, int decimalPlaces=6);
-	explicit String(double, int decimalPlaces=6);
+	explicit String(float, int decimalPlaces=2);
+	explicit String(double, int decimalPlaces=2);
 	~String(void);
 
 	// memory management
diff --git a/hardware/arduino/sam/cores/arduino/WString.cpp b/hardware/arduino/sam/cores/arduino/WString.cpp
index de1a2f1b2..d6b344c2a 100644
--- a/hardware/arduino/sam/cores/arduino/WString.cpp
+++ b/hardware/arduino/sam/cores/arduino/WString.cpp
@@ -326,14 +326,14 @@ unsigned char String::concat(unsigned long num)
 unsigned char String::concat(float num)
 {
 	char buf[20];
-	char* string = dtostrf(num, 8, 6, buf);
+	char* string = dtostrf(num, 8, 2, buf);
 	return concat(string, strlen(string));
 }
 
 unsigned char String::concat(double num)
 {
 	char buf[20];
-	char* string = dtostrf(num, 8, 6, buf);
+	char* string = dtostrf(num, 8, 2, buf);
 	return concat(string, strlen(string));
 }
 
diff --git a/hardware/arduino/sam/cores/arduino/WString.h b/hardware/arduino/sam/cores/arduino/WString.h
index 4b9e64e0b..0404f767a 100644
--- a/hardware/arduino/sam/cores/arduino/WString.h
+++ b/hardware/arduino/sam/cores/arduino/WString.h
@@ -69,8 +69,8 @@ public:
 	explicit String(unsigned int, unsigned char base=10);
 	explicit String(long, unsigned char base=10);
 	explicit String(unsigned long, unsigned char base=10);
-	explicit String(float, int decimalPlaces=6);
-	explicit String(double, int decimalPlaces=6);
+	explicit String(float, int decimalPlaces=2);
+	explicit String(double, int decimalPlaces=2);
 	~String(void);
 
 	// memory management